Wellhead stuffing box support assembly

• US 20030127220A1
• Filed: 01/04/2002
• Published: 07/10/2003
• Est. Priority Date: 01/04/2002
• Status: Active Grant

• Current Assignee: Daniel J. Riddell, Keith D. Farquharson
• Original Assignee: Daniel J. Riddell, Keith D. Farquharson
• Inventors: Farquharson, Keith D., Riddell, Daniel J.
• Granted Patent: US 6,637,509 B2
• Time in Patent Office: Days
• US Class Current: 166/86.3
• CPC Class Codes: E21B 33/08 Wipers; Oil savers
• CPC Class Codes: E21B 43/127 Adaptations of walking-beam pump systems
• CPC Class Codes: F04B 47/026 Pull rods, full rod component parts
• CPC Class Codes: F04B 53/164 Stoffing boxes
• CPC Class Codes: F16J 15/187 Self-aligning stuffing-boxes

Abstract

The support assembly functions like a joint between the wellhead production tree and the stuffing box. The joint can tilt or move laterally to maintain coaxial relationship between the stuffing box and the polished rod extending therethrough.

Claims

1. A support assembly, for connection between the upper end of a production pumping tree and the lower end of a stuffing box and through which a polished rod will extend, comprising:

a tubular lower housing having a side wall and upper and lower ends, the side wall forming a central bore therethrough, the bore having a lower portion and an expanded diameter upper portion, the side wall forming an annular flat internal shoulder at the junction of the upper and lower bore portions;

a lower ring, having a flat bottom surface and a spherically curved top surface, seated on the shoulder, the lower ring having a central opening of sufficient diameter to accommodate the polished rod with a lateral clearance, the lower ring having a lateral clearance with the side wall of the lower housing;

an upper housing comprising a tubular main body having upper and lower ends, the body lower end having an outwardly protruding flange, the flange being positioned in the upper portion of the lower housing bore and being seated on the lower ring, the flange having spherically curved upper and lower surfaces having a common center, the flange lower surface conforming to the top surface of the lower ring, the main body having a central bore extending therethrough for accommodating the polished rod, the flange having a lateral clearance with the lower housing side wall;

an upper ring seated on the flange, the upper ring having a spherically curved bottom surface for conforming with and contacting the flange upper surface to retain the flange against upward movement, the upper ring having a lateral clearance with the side wall of the lower housing;

an annular cap attached to the upper end of the lower housing, the cap having a transverse wall having a bottom surface retaining the rings and flange within the expanded diameter upper portion of the lower housing bore, the cap wall forming a central opening through which the main body of the upper housing extends with a lateral clearance; and

means for centralizing the polished rod within the main body;

whereby the upper housing may tilt coaxially with the polished rod and move laterally to a limited extent.

2. The support assembly as set forth in claim 1 wherein the diameter of the central opening of the lower ring is smaller than the diameter of the lower portion of the lower housing bore, so that the lower ring overhangs and extends part-way across the top end of the lower portion;

and comprising

closure means, suspended from the bottom surface of the lower ring, for automatically closing the lower ring central opening when the polished rod is not extending therethrough.

3. The support assembly as set forth in claim 3, wherein:

the lower housing side wall internal shoulder, lower ring bottom surface, upper ring top surface and the cap transverse wall bottom surface are all horizontal;

said support assembly comprising;

means for sealing the support assembly to prevent the upward escape of fluid therethrough.